Nowhere else in the United States can a visitor see so much alpine country with such ease. A mere two-hour drive from Denver, Trail Ridge Road takes visitors into the heart of Rocky Mountain National Park, traversing a ridge above 11,000 feet for 10 miles. Along the way, tiny tundra flowers and other wild blooms contrast with sweeping vistas of towering summits; 78 of them exceed 12,000 feet. Alpine lakes reflect the grandeur.

The summits form at least the third generation of mountains to rise in this region. The first probably protruded as islands above a shallow sea more than 135 million years ago, when dinosaurs reigned. Another range grew out of a later sea some 75 million years ago. Over the eons these summits eroded to rolling hills, which rose once again, although unevenly: Some portions sank along fault lines, helping create the striking texture of the current scenery.

Rock as old as that at the bottom of the Grand Canyon—nearly two billion years—caps the Rockies' summits. Within the last million years, glaciers, grinding boulders beneath them, carved deep canyons. Erosion later scoured the more jagged summits into their present profiles.

Rocky Mountain, though only about an eighth the size of Yellowstone, accommodates as many visitors—three million or so a year. Overcrowding worries park officials and conservationists, who cite distressed animals, trodden plants, and eroded trails. Condominium development is crowding the park's borders also, shrinking the habitats of elk and other wildlife and threatening to turn the park into an island of nature.

How to Get There

Take I-25 north from Denver (about 77 miles away) or south from Cheyenne, Wyoming (about 90 miles away), then US 34 west at Loveland. From the west, pick up US 34 at Granby. Airport: Denver.

When to Go

If you go from mid-June to mid-August be prepared to share the park with lots of other visitors. If you plan ahead and visit the park early in the morning or late in the day you'll avoid some of the crowds. Willing and able to hike more than 3 miles in to the backcountry? You'll experience much more solitude. Trail Ridge Road stays open from roughly late May to mid-October; trails thaw out by around July 4. In May, sub-alpine wildflowers bloom; in early July, the tundra flowers. September, the sunniest month, is a prime time to visit: Elk move to lower elevations, and you can hear their mating bugles. The tundra turns crimson early in the month; aspens turn golden later. In the winter there is cross-country skiing and snowshoeing.

How to Visit

On a one-day blitz from the East Entrance, drive Trail Ridge Road as far as Farview Curve for the classic overview of the park's mountains, valleys, and tundra. If you wish, make a loop of the first leg by driving one-way, unpaved Old Fall River Road west, then Trail Ridge Road east. Old Fall River Road gives you an intimate look at a wooded mountainside, but it's usually closed by snow until early July. (Neither Old Fall River Road or Trail Ridge Road have guardrails or shoulders, and are very winding.) With more time, drive all the way to Grand Lake on the west side the first day, then take your trip to Bear Lake the second day. Spend extra time on the excellent nature trails and day hikes.

If you go in summer and plan to backpack and hike, be sure not to be caught above timberline between about 12 and 4 p.m., when lightning storms are frequent.